The Darkroom Sink (Part II)

Part II

In part one, I designed, built and assembled the sink with specialised plywood from my local DIY outlet. Now the real work begins. In the final part of the process, the sinks plumbing and waterproofing is dealt with. I outline and give instructions for each stage. Hopefully the instructions will help you build your own darkroom sink too!

Darkroom Sink with Jobo and Trays
Darkroom Sink with Jobo and Trays



Making the sink plughole

This will required cutting a hole into the bottom panel not a task for the faint hearted. I used a router to make a 3mm inset around the plughole so it sits flush. Best to watch the video on this to see it exactly.  When choosing a plughole assembly, pick something straightforward. Keep in mind the sinks wood panel is 21mm thick.



*Use a test piece of wood to calibrate you insets for the plughole before attempting to work on the sinks bottom panel.

  1. Cut the hole for the plug hole and ensure it fits using a drill saw hole bit.
  2. Use a template and set the router to remove 2-3mm so the plughole is sunken into the sink.
  3. Round the edge with 10 or 12 mm rounded router bit.

Part List

  1. Plughole assembly
  2. Drill Saw Hole Set
  3. Router and Router Bit Set

Sealing the sink with epoxy and filler

It’s important to wear gloves as epoxy resin shouldn’t make contact with your skin. I recommend using some thick washing up gloves, I did try the normal nitrile gloves which I use for the darkroom work but they ripped so often, I switched over to the thicker washing up ones.

Also you’ll need a new brush for each session!

Epoxy and Brushes
Epoxy and Brushes


Darkroom sink seams sealed with epoxy filler
Darkroom sink seams sealed with epoxy filler

I did use calcium carbonate initially,  as already have some in my darkroom for cleaning glass plates for wet plate collodion.  However I ended up using the West System 406 over the my initial attempt. The West System 406 is so much better and fit for purpose over calcium carbonate.


  1. Layer down the glass fibre webbing and apply the first coat of epoxy with a plastic spreader or paint brush.
  2. After 24 hours of curing, sand down the entire sink. This will help the bonding when the second epoxy coat is applied.
  3. Seal the corners with an epoxy resin filler mix. I’m using West System 406 mixed into my epoxy to make a peanut butter consistency.
  4. Apply the second coat of epoxy.

Sealing the seams of the sink

The seams and joints need attention to ensure that they are well sealed against water leaks. You’ll need to use an epoxy filler for this like West System 406.  To hide my initial messy filling and sealing of the sink, I coloured the epoxy with “Silver Black” pigment powder into the epoxy resin which I highly recommend

  1. First measure out part A + B of the epoxy and mix it well.
  2. Then add a scoop of pigment powder to get the colour you wish. Again mix well.
  3. Finally add in the filler powder and mix well. The consistency should be like peanut butter so it sticks and holds well in the seams and corners.


Part List

  1. Putty scraper and plastic spreaders
  2. Brushes to apply epoxy.
  3. “Silver Black” pigment powder
  4. 5m² glass woven material for epoxy
  5. 4.5kg of epoxy resin
  6. West System 406 filler
  7. Bosch Sander

Approx costs

Item Description Approx. €/$
Plywood panels, glue and screws 300
5kg Epoxy, webbing and brushes 75,00
Sink Plughole 10,00
Piping, U-bend, etc.. 20,00
West System 406 20,00
Total 425,00


Darkroom Sink with Jobo and Trays
Darkroom Sink with Jobo and Trays


Now that the sink is finally plumbed into drain which seemed harder than it actually was, after some wrangling and overthinking the problem out too much, a visited to the local DIY hardware outlet resolved most, if not all of my concerns. Currently I’m still using a hose pipe connected to my existing sink for water right now but once I have time I’ll tackled that issue another time. For now at least, I’ve again have a working darkroom and ready to produce artwork once again, I’m excited!

The video of construction and applying epoxy in two part is now finished too. A mammoth undertaking for a mammoth size sink. What I can say I already feel the relief of having more space to work with without the worry of water going into place where it shouldn’t.

I feel some alternative photography work is on the cards, such as Cyanotype or even VanDyke Brown or maybe some traditional prints at least that’s the plan.

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